Journal of Physics B Atomic Molecular and Optical Physics

Double radio-optical resonance in87RB atomic vapour in a finite-size bufferless cell

Andrey Litvinov, Georgy A. Kazakov, Boris G. Matisov, I. E. Mazets

Published Jun 9, 2008• 16 citations

Abstract

We study theoretically the formation of a double radio-optical resonance (DROR) in 87 Rb vapour in a cell with an anti-relaxation coating. We develop a quantum-kinetic approach to the study of the Dicke narrowing. We examine various DROR schemes for different polarizations of the laser radiation. We find that the short-term stability σy of a DROR-based frequency standard improves significantly (by an order of magnitude) if a laser with a broad spectrum is used, in comparison to the case of excitation by a narrow-band laser radiation, and reaches ultimately the value σy ∼ 1 × 10 −14 τ −1/2 , where τ is the integration time (in seconds).

DOI: 10.1088/0953-4075/41/12/125401

Related papers

Double radiooptical resonance in 87Rb atomic vapor in cells with antirelaxation wall coating

A. N. Litvinov, Georgy A. Kazakov, Boris G. Matisov +1 more

The object of investigation is double radiooptic resonance in 87 Rb atomic vapor contained in a cell covered by an antirelaxation coating. The Dicke narrowing is studied in terms of the quantum-kinetic approach. It is found that optical pumping using a laser with a “wide” radiation spectrum makes it possible to improve the short-term stability of the frequency standard by an order of magnitude compared with a narrow-spectrum laser.

Technical PhysicsFeb 1, 20092 citations

Double radio–optical resonance in alkali metal vapors subjected to laser excitation

L. A. Budkin, V. L. Velichanskiǐ, Alexander S. Zibrov +3 more

An investigation was made of a double radio–optical resonance (DROR) in a multilevel system of the alkali metal type. Equations for the density matrix were solved to obtain expressions for the signal, DROR line width, and shift of the maximum of DROR line peak. A study was made of the principal characteristics of a DROR in an optically dense medium in the form of a rubidium vapor. The ultimate short-term frequency instability of a rubidium discriminator was estimated to be 2 × 10 − 14 t − 1/2 . Several experiments were carried out using an injection laser as an optical pump source. The results of the measurements yielded a short-term instability of 3 × 10 − 12 t − 1/2 . An investigation was made of the optical frequency shift and an anomalous dependence of the shift on the intensity was observed. The results of the experimental and theoretical investigations were compared. The requirements for stabilization of the DROR parameters needed to reduce the frequency instability of a rubidium discriminator to the 10 − 14 level were identified.

Soviet Journal of Quantum ElectronicsMar 31, 19909 citations

Double-resonance studies on compact, high-performance rubidium cell frequency standards

Thejesh Bandi Nagabhushan

This thesis presents experimental studies on continuous-wave (CW) laser-microwave double-resonance (DR) spectroscopy and metrology in rubidium (87Rb) vapor cells in view of new high-performance, compact Rb-cell atomic clocks. The Rb vapor cell is confined inside a magnetron-type cavity microwave resonator (MWR). The CW DR spectroscopy involves two resonant electromagnetic fields that are operated simultaneously to interrogate the atoms - the optical field to polarize the atoms by optical pumping, and the microwave field to drive the ground-state hyperfine clock transition that serves as an atomic frequency reference. Details on characterization of compact laser heads and microwave synthesizers used in this work are presented. The vapor cell standards are useful in our everyday lives for applications ranging from telecommunications, navigation, metrology etc. In view of improving the performances of the Rb cell standards, two different clock approaches were studied in detail: The first one is on use of vapor cells (1.4 cm3) whose inner walls are coated with anti-relaxation material. A first ever wall-coated cell clock was demonstrated with good short-term frequency stability. The medium- to long-term stability was found to be limited by the temperature coefficient (TC) of the coating material itself. This work gave the insight to important features to be considered in future anti-relaxation coating materials for atomic standards. The second novel approach involves using a bigger cell (12 cm3) within a newly developed, improved MWR towards a high-performance atomic standard. Adopting a larger cell gives a higher atomic Q-factor signal that improves the short-term clock stability. In this approach, the cell was filled with 87Rb and buffer gases. With this clock, we demonstrate the state-of-the-art short-term stability of <1.4×10−13 τ−1/2. Metrological quantitative measurements on parameters influencing the medium- to long-term stability were studied in view of next generation satellite navigation systems that demand a stability level of <1×10−14 at 10 4 s (equivalent to <1 ns/day). The potential of short-term stability and understanding of the limiting factors on medium- to long-term time scales demonstrated in this study pave the way for future work towards the commercialization of high-performance Rb atomic clocks for a variety of applications.

Jan 1, 20132 citations

Double-resonance studies on compact, high-performance rubidium cell frequency standards

Thejesh Bandi

This thesis presents experimental studies on continuous-wave (CW) laser-microwave double-resonance (DR) spectroscopy and metrology in rubidium (87Rb) vapor cells in view of new high-performance, compact Rb-cell atomic clocks. The Rb vapor cell is confined inside a magnetron-type cavity microwave resonator (MWR). The CW DR spectroscopy involves two resonant electromagnetic fields that are operated simultaneously to interrogate the atoms - the optical field to polarize the atoms by optical pumping, and the microwave field to drive the ground-state hyperfine clock transition that serves as an atomic frequency reference. Details on characterization of compact laser heads and microwave synthesizers used in this work are presented. The vapor cell standards are useful in our everyday lives for applications ranging from telecommunications, navigation, metrology etc. In view of improving the performances of the Rb cell standards, two different clock approaches were studied in detail: The first one is on use of vapor cells (1.4 cm3) whose inner walls are coated with anti-relaxation material. A first ever wall-coated cell clock was demonstrated with good short-term frequency stability. The medium- to long-term stability was found to be limited by the temperature coefficient (TC) of the coating material itself. This work gave the insight to important features to be considered in future anti-relaxation coating materials for atomic standards. The second novel approach involves using a bigger cell (12 cm3) within a newly developed, improved MWR towards a high-performance atomic standard. Adopting a larger cell gives a higher atomic Q-factor signal that improves the short-term clock stability. In this approach, the cell was filled with 87Rb and buffer gases. With this clock, we demonstrate the state-of-the-art short-term stability of <1.4Ã10â13 τâ1/2. Metrological quantitative measurements on parameters influencing the medium- to long-term stability were studied in view of next generation satellite navigation systems that demand a stability level of <1Ã10â14 at 10 4 s (equivalent to <1 ns/day). The potential of short-term stability and understanding of the limiting factors on medium- to long-term time scales demonstrated in this study pave the way for future work towards the commercialization of high-performance Rb atomic clocks for a variety of applications.

Jan 1, 20134 citations

Raman–Ramsey pulsed excitation of coherent population trapping resonances in a 87Rb cell with a buffer gas

V. N. Baryshev, G. V. Osipenko, M. S. Aleinikov +1 more

We report the results of experimental investigation of the Raman – Ramsey method of pulsed excitation of coherent population trapping (CPT) resonances in a rubidium vapour cell filled with a mixture of Ar and Ne buffer gases. For the development of compact quantum microwave frequency standards, this method is an alternative to the pulsed optical pumping method recently implemented using the same rubidium cell. Both methods have advantages over the traditional double radio-optical resonance technique, the main of which is the substantial suppression of the light shift of the clock transition frequency, since the evolution of the coherence of atomic states forming the clock transition occurs in the absence of laser radiation in the cell. The narrow (110 – 240 Hz) Raman – Ramsey resonances are obtained using the scheme of pulsed excitation of CPT resonances on the D 1 lines of the 87 Rb atom with the same linear (lin||lin) polarisations of the bichromatic laser radiation components. The process of optimising the central fringe linewidth, its contrast, and the linewidth-to-contrast ratio is described. The magnetic dependence of the Raman – Ramsey line central fringe linewidth is experimentally investigated.

Quantum ElectronicsMar 1, 20196 citations

Coherent population trapping in a finite-size buffer-less cell

Georgy A. Kazakov, Boris G. Matisov, Andrey Litvinov +1 more

We have investigated theoretically the formation of a coherent population trapping resonance in a finite-size vapour cell without a buffer gas. We have demonstrated the novel mechanisms of the resonance narrowing: an analogue of the Dicke effect and light-induced narrowing. In the light-induced narrowing regime the parameters of the coherent population trapping resonance weakly depend on the cell size and the type of coating.

Journal of Physics B Atomic Molecular and Optical PhysicsSep 19, 200724 citations

This thesis presents experimental studies on continuous-wave (CW) laser-microwave double-resonance (DR) spectroscopy and metrology in rubidium (87Rb) vapor cells in view of new high-performance, compact Rb-cell atomic clocks. The Rb vapor cell is confined inside a magnetron-type cavity microwave resonator (MWR). The CW DR spectroscopy involves two resonant electromagnetic fields that are operated simultaneously to interrogate the atoms - the optical field to polarize the atoms by optical pumping, and the microwave field to drive the ground-state hyperfine clock transition that serves as an atomic frequency reference. Details on characterization of compact laser heads and microwave synthesizers used in this work are presented. The vapor cell standards are useful in our everyday lives for applications ranging from telecommunications, navigation, metrology etc. In view of improving the performances of the Rb cell standards, two different clock approaches were studied in detail: The first one is on use of vapor cells (1.4 cm3) whose inner walls are coated with anti-relaxation material. A first ever wall-coated cell clock was demonstrated with good short-term frequency stability. The medium- to long-term stability was found to be limited by the temperature coefficient (TC) of the coating material itself. This work gave the insight to important features to be considered in future anti-relaxation coating materials for atomic standards. The second novel approach involves using a bigger cell (12 cm3) within a newly developed, improved MWR towards a high-performance atomic standard. Adopting a larger cell gives a higher atomic Q-factor signal that improves the short-term clock stability. In this approach, the cell was filled with 87Rb and buffer gases. With this clock, we demonstrate the state-of-the-art short-term stability of <1.4Ã10â13 τâ1/2. Metrological quantitative measurements on parameters influencing the medium- to long-term stability were studied in view of next generation satellite navigation systems that demand a stability level of <1Ã10â14 at 10 4 s (equivalent to <1 ns/day). The potential of short-term stability and understanding of the limiting factors on medium- to long-term time scales demonstrated in this study pave the way for future work towards the commercialization of high-performance Rb atomic clocks for a variety of applications.